Die-stock for cutting tapered threads.



H. W. OSTER.

DIE STOOK FOB. CUTTING TAPBRBD THREADS.

APPLICATION FILED PEB.12,190H.

977,539 Patented Dec. 6, 1910.

6 BHBETS BHEET 1.

In: NORRIS PETERS co). wasumororv. n. c

H. W. OSTER. DIE STOCK FOB CUTTING TAPEBED THREADS. rum-nun FILEDFEB-12,1908.

977,539. Patented Dec. 6, 1910.

6 8HEETB-SHEET 2.

H. W. OSTER.

DIE STOCK FOR CUTTING TAPBRED THREADS.

APPLIUATION FILED FEB. 12,1908.

Patented Dec.6,19l0.

6 BHEET8-SHEET 3.

H. W. OSTER.

DIE STOCK FOB CUTTING TAPERED THREADS.

APPLICATION FILED PEB.12,1908.

Patented Dec. 6, 1910.

6 BHEETBSHEET 4.

Wh @WW 7. 56226 we i THE Nurms PETERS cm, WASHINGTON, a c

H. W. OSTER.

DIE STOCK FOR CUTTING TAPERED THREADS.

APPLICATION FILED I'EB.12, 1908.

977,539. Patented Dec. 6, 1910.

5 SHEET8-BHEET 5.

ww MMM UNITED STATES PATENT OFFICE.

HERMAN W. OSTER, OF CLEVELAND, OHIO, ASSIGNOR TO THE OSTER MANUFACTURINGCOMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

DIE-STOCK FOR CUTTING TAPERED THREADS.

Specification of Letters Patent.

Patented Dec. 6, 1910.

Application filed February 12, 1908. Serial No. 415,480.

1 '0 all whom it may concern:

Be it known that I, HERMAN W. Os'rnn, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Die-Stocks for CuttingTapered Threads, of which the following is a full, clear, and exactdescription.

This invention has for its object the production of a novel die stockcapable of cutting tapered threads, and having a wide range of easilyeffected adjustment whereby it may be used on pipes of differentdianieters.

The invention, embodied in an efficient device, is shown in theaccompanying; drawings and is hereinafter described and definitelypointed out in the claims.

In said drawing Figure 1 is an end View of a die stock embodying theinvention with a portion of the cam plate and cap ring broken away. Fig.2 is a longitudinal sectional view on line 2 2 of Fig. 1. Fig. 3 is aview of the inner face of the cam plate H. Fig. 4 is a sectional view online fh-T of Fig. 3; Fig. 5 is a sectional view on line 55 of Fig. 3.Fig. 6 is an end view of the clamping part of the device. Fig. 7 is aside view, partly sectioned, of the parts thereon in Fig. 6. Fig. 8 isan end view of the cam plate; and Fig. 9 is an end view of the member E.

Referring to the parts by letters, A represents the die-carrying head,in the end face of which are radial grooves wherein the radially movabledies or chasers B are held by a cap ring 0, this ring being secured tothe end of the head by screws 0 or other suitable means. This head istubular and has a longitudinally extended barrelawhich is externallythreaded, the pitch of said threads corresponding with the pitch of thecutting threads on the dies. This threaded portion screws into a sleeveD which is fixed to the tubular member E,these two pieces D and Econstituting the work holder. Any suitable means, as for example, suchas are hereinafter described, may be employed for fastening the workholder on the pipe to be threaded. The operating ring G is rotatablymounted on said work holder with its lower edge fitted into an annulargroove in said Work holder, said groove being formed between the end ofthe member E and an annular flange (Z on the member D. The ring G- maybe rotated upon the work holder, but is by reason of the describedconstruction prevented from moving endwise relative thereto. The sockets51 formed on this ring are for the reception of handles by which thering may be turned.

The dies B are adjusted radially in and out by a cam plate H having onits inner face cam grooves ]z.,--as many as there are dies. ProjectionsZ) on the dies extend into these grooves. The outer wall of each ofthese grooves is formed by a long flange or rib it whose inner surface71 is tapered as shown; that is to say, this inner surface is so shapedthat any radial plane will intersect it in a line which is inclined tothe aXis of the head, and which diverges there from as it goes away fromthe cam plate C. A portion of the outer face of each rib 72. iscylindrical as at 71 thereby forming an incomplete cylinder which isrotatably mounted in the end of the operating ring G.

To adjust the radial position of the dies, therefore, it is onlynecessary to turn this cam plate relative to the die carrying head. Whenthe dies have been properly adjusted the cam plate is to be clamped tothe ring G. Any suitable means may be employed for this purpose, themeans shown consisting of screws J which screw into the ring and havelarge heads which overhang and engage with the outer face of the camplate. WVhen the screws are screwed in, the cam plate is clamped betweensaid heads and a little annular flange g on the ring. It will be notedthat the outer ends of the dies are tapered to correspond with the taperof the surfaces 71, against which the outer ends of said dies bear atall times.

Suitable means are provided for compelling the head A and ring G torotate together, but for permitting the head to move longitudinallyrelative to the ring. The means employed consist of pins K secured tothe ring G in positions parallel with the axis of the head, said pinspassing freely through holes a in the head.

To use the described device the work holder is secured upon the pipe tobe threaded. The cam plate is turned to adjust the dies into the properposition and is then clamped to the operating ring. The latter is thenturned, but cannot move endwise.

The head A turns with said ring, but since it screws into the workholder must move longitudinally relative thereto. In so moving itcarries the dies which, as they move longitudinally relative to thesurface if, are permitted to recede radially, whereby they cut a taperedthread which corresponds with the taper of said surface.

As before stated, any suitable means may be provided for clamping thedevice upon the pipe to be threaded, but the specific mechanism shown isadmirably adapted for the purpose and contains a certain novel featureof construction which it is desired to cover in this patent.

The member E of the work holder is provided, in its end, with radialgrooves for the reception of the movable clamping dies M. A cam plate Nis rotatably mounted about a cylindrical flange c which is a part of themember E; and this cam plate is held in place by aflanged ring P whichis screwed into the flange e. The cam plate N has the cam groove n whichreceives projections m on the dies M. The upper edge of the cam plate Nis knurled so that it may be easily turned. A clamping screw R passes upthrough an arc-shaped slot (2 in the projecting flange e of the member Eand screws into the cam plate N. This screw is provided with anoperating handle 7'. When the cam plate has been turned to bring theclamping dies into proper position, it is clamped to the member E bymeans of the screw R.

There is a longitudinal hole passing entirely through one of theclamping dies M. Through this hole a clamping screw T is screwed. hen,by turning the cam plate N, the clamping dies have been movedintoengagement with the pipe or other cylindrical device to be threaded,the cam plate is locked in position through the action of the screw R.It is, however, difficult to cause these clamping dies to press withsuch force upon the pipe that, when the threads are being cut on thepipe, the device will not turn upon said pipe. It is to prevent thisaction that said screw T is provided; for when the dies M are caused toimpinge as tightly as practicable upon the pipe, this set screw is thenscrewed in and thereby the pipe is clamped so firmly that the devicecannot turn thereon.

Having described my invention, I claim:

1. The combination of a tubular threaded work-holder, a die head whichhas threads en a ing with those on said work holder, ra ia. ly movabledies carried by said head, a cam plate having longitudinally tapered camsurfaces which said dies engage, which plate is capable of being turnedrelative to said head to adjust the position of said dies,

means connecting said head and plate to compel them to rotate in unison,and means preventing the longitudinal movement of said plate.

2. The combimltion of a tubular threaded work holder, a die head whichhas threads engaging with those on said work holder, a cam plate capableof being turned rela tive to said head and having cam grooves, the outerwalls of which are tapered, radially movable dies carried by said headhaving projections which enter said grooves, the outer ends of said diesbeing in contact with said tapered surfaces, means compelling the camplate to turn with said head, and means preventing longitudinal movementofsaid cam plate.

The combination of a tubular threaded work holder, a die head which hasthreads engaging with those on said work holder, radially movable diescarried by said head, an operating ring rotatably mounted on said workholder, means preventing endwise movement of said ring, a plate havingtapered surfaces with which the outer ends of said dies engage, meansfor fastening said plate to said operating ring, and means transmittingrotary motion from said operating ring to said head.

l. The combination of a tubular threaded work holder, a die head whichhas threads engaging with those on said work holder, and haslongitudinal holes, radially movable dies carried by said head, anoperating ring rotatably mounted on said work holder, means pr ventingendwise movement of said ring, longitudinally extended pins secured tothe ring and loosely fitted to said holes, a plate having tapered camsurfaces with which the .outer ends of said dies engage, means forfastening said plate to said operating ring, and means transmittingrotary motion from said operating ring to said head.

5. The combination of a tubular threaded work holder, a die head whichhas threads engaging with those on said work holder, and haslongitudinal holes, radially movable dies carried by said head, anoperating ring rotatably mounted on said work holder, means preventingendwise movement of said ring, a plate having tapered cam surfaces withwhich the outer ends of said dies engage, means for fastening said plateto said operating ring, and pins secured to said ring and looselyentering the holes in the die head.

6. The combination of a tubular work holder, a co-axial die head capableof being rotated and of being moved lon itudinally relative to the workholder, radial y movable dies carried by said head, a co-axial cam platehaving longitudinally tapered cam surfaces with which said dies en age,which In testimony whereof, I hereunto aflix my plate is capable ofbeing turned relative to signature in the presence of two Witnesses.said die head to adjust the dies means for p 1 connecting said cam plateand die head to HELMAN OSTEI" 5 compel them to rotate in unison, andmeans W itnesses:

preventing the longitudinal movement of E. B. GILOHRIST,

the cam plate relative to the Work holder. H. R. SULLIVAN.

